Locking device



J. GARDNER LOCKING DEVICE July 26, 1955 Filed July 3, 1953 Fig. 6

R. S MM Y m E W M G T T S A E M M A J Y B /2 4 7 4 3 5 4 2 l I F 2 2 LOCKING DEVICE James Gardner, Alameda, Calif.

Application July 3, 1953, Serial No. 366,080

4 Claims. (Cl. 292-178) (Granted under Title 35, U. S. Code (1952), see. 266) 'Ijhe invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

This invention relates to bolt type locking devices and is particularly concerned with a latch bolt lock employed especially on heavy closure members such as aircraft hangar doors.

Spring actuated bolt type locking devices are of course well known in the art, as illustrated in U. S. Patents 89,191; 1,510,562; 1,580,611; and 2,547,315. However, prior art devices of this nature are unsatisfactory for use with massive and heavy doors such as those of aircraft hangars because of the ease with which the bolt of such locks may be broken or bent out of shape as the result of careless handling of the doors to which they are attached. Thus, for example, should a conventional latch bolt lock attached to a large hangar door be accidentally or carelessly left in latching position with the door open so that the bolt is extended outside its barrel or housing and the door slammed against its frame, the outer exposed end of the bolt is often seriously damaged from the sharp blow to which it is accordingly subjected, resulting in expense for repairs or replacements.

One object of this invention is to provide a locking device particularly useful on large and heavy closures such as hangar doors.

nited States Patent I A particular object is the provision of a latch bolt lock for attachment to such closures, the bolt of which will automatically release to the unlatched position within the bolt housing without damage if such closure is forced against its frame with the bolt in extended latching position.

Yet another object is to provide a locking device which employs a minimum of parts, is easily and inexpensively produced, and is sturdy and reliable in operation.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

Fig. 1 is an isometric view of the invention device,

Fig. 2 is a plan view of the device of Fig. 1, with certain The housing and channel are open at one end 16 for movement of the bolt to its extended latching position shown in Figs. 1 to 3. Housing 10 has flanges 18 along opposite sides thereof for securement by means of bolts 20 to a flanged support member 22 in turn adapted to be attached along the edge of a closure such as a hangar door by means of fasteners (not shown) passing through apertures 24.

A longitudinal slot 26 is formed in the top 28 of the housing near the closed end 30 thereof, the slot having an enlarged arcuate portion 32 at its forward end and a narrower elongated portion 33 extending to the rear. An arcuately shaped support member or portion 34 formed integral with the top of the housing is positioned around the inner periphery of the enlarged portion of the slot, such support member being depressed below the top surface of the housing to form a recess 36 therein. The function of the foregoing slot structure will be fully explained below.

As previously noted, latch bolt 14 is positioned for slidable movement within channel 12, and has an elongated shank portion 38 spaced from the inside surfaces of the housing and disposed at all times within channel 12 thereof, and a tongue 40 at one end adjacent the open end of the housing, the tongue being extendable outwardly beyond the open end of the housing and channel to latching position, as shown in Figures 1 to 3 of the drawing, and retractable to a position entirely within the housing, corresponding to the unlatched or open position. The opposite end of latch bolt 14 terminates in a body member 42 in which is threadably secured one end of a screw 44 positioned with its axis normal to the axis of the bolt and extending through slot 26 externally of the housing. Stop members or lugs 45 attached to the inside surface of housing 10 and to the top of support member 22 intermediate the ends of the housing extend into channel 12. A compression spring 47 is positioned around the inner portion of bolt 14, the ends of said spring abutting lugs 45 and body member 42 at the end of the bolt. Spring 47 tends to urge latch bolt 14 including body member 42 toward the rear or closed end 30 of housing 10.

A sleeve 46 encircles the portion of screw 44 external of the housing and has a lower portion 48 in slidable engagement with the screw, an upper portion 50 terminating at its top above the head 52 of the screw in a circular knob 54 having its sides knurled as at 56 for gripping with the fingers when it is desired to manually manipulate the bolt, for example into latching position as seen in Figs. 1 to 3. The inside surface of mid-portion 58 of sleeve 46 is spaced from the adjacent sides of screw 44. As particularly seen in Fig. 4, the lower portion 48 of the sleeve terminates in an annular member 60 having an Fig. 5 is an enlarged sectional view of a modification of the feature of Fig. 4, and

Fig. 6 is a plan view of the structure of Fig. 5, with certain parts removed.

In Figures 1 to 4 of the drawing, illustrating a preouter diameter smaller than that of said sleeve, the diameter of the bottom portion of member 60 being somewhat smaller than the diameter of the enlarged portion of slot 26. Said annular member forms a shoulder 62 at its base 7 adapted to rest on depressed support member 34 in the enlarged portion 32 of slot 26, or on the surface of top 28 of the housing along the edges of the elongated portion 33 of the slot when the screw enters this latter portion. A compression spring 64 is positioned in space 66 within sleeve 46, said spring encircling screw 44 and abutting the inside surface of the lower portion 48 of the screw and the lower surface of the screw, head 52. It is thus seen that spring 64 tends to urge shoulder 62 of sleeve 46 into seating engagement against support member 34 of recess 36, or into contact with the upper surface of the housing adjacent the elongated portion 33 of slot.

26 when the screw is withdrawn from such recess, as described below. a

An important feature of the invention is'the cooperating structure between shoulder 62 of sleeve 46, and recess 36 in the enlarged portion 32 of slot 26, in conjunction with the double spring action of the device, enabling the latch bolt to spring back from its extended latching position to the retracted position with tongue 49 thereof withdrawn inside the housing, on the application of a force against the extended tongue. In order to perform the above function, the depressed support member 34 within the enlarged portion 32 of slot 26 is gently curved upwardly at its ends 70 adjacent the narrower longitudinal portion 33 'of the slot, and shoulder 62 of sleeve 46 is also curved at its outer edge 72.

Curved ends 70 of support member 34 and curved edge 72 of shoulder 62 form cooperating camming surfaces so that when screw 44 and its associated sleeve 46 are aligned with the enlarged portion 32 of slot 26, with spring 64 urging the shoulder 62 of the sleeve downwardly into contact with support member 34, shoulder 62 will be sufficiently wedged within recess 36 to hold the latch bolt attached to screw 44 in outwardly extended latching position against the action of spring 47. However, the curvature of the foregoing camming surfaces 70 and 72 is such that when the outwardly extended tongue of bolt 14 is subjected to a force having an inward longitudinal component of sufficient magnitude, such as may be delivered by a sharp blow as when a door having the invention device attached thereto is slammed against its frame, the camming surfaces will slidably disengage and the shoulder 62 and sleeve 46 will first be urged upwardly against the action of spring 64 until such shoulder makes contact with the adjacent end of the elongated portion 33 of slot 26, after which the screw 44 and its associated sleeve spring back through the action of spring 47 to the rear end of the elongated portion of slot 26 to the position shown in dotted lines in Fig. 3, during which time the shoulder 62 of the sleeve slides along the upper surface of the housing adjacent the edges of the slot. Movement of the screw to this position at the rear of slot 26 in turn urges the latch bolt in the same direction, thereby withdrawing the tongue 40 thereof into unlatched protected position within the housing 10, as shown in dotted lines in Fig. 3.

If desired, the curved edge 72 of shoulder 62 of the sleeve and/ or curved ends 70 of support member 34 may be roughened to provide stronger frictional engagement and camming action between these cooperating surfaces.

In a modification of the cooperating structure between shoulder 62 of sleeve 46 and recess 36 of slot 26 described above, as shown in Figs. 5 and 6 support member 34 of the device of Figs. 1 to 4 may be eliminated entirely, and the edge 74 itself of the enlarged portion 76 of slot 73 closely adjacent the elongated portion thereof, given a rounded concave contour adapted to fit the convex curvature of the edge 72 of shoulder 62, so that when screw 44 and its associated sleeve 46 are aligned with the enlarged portion 76 of slot 78, curved edge 74 will function both as a support for shoulder 62 of the sleeve and as a camming surface in conjunction with curved edge 72 of the shoulder to maintain the screw in this position until urged out of the enlarged portion 76 of the slot in the manner above described.

From the foregoing, it is seen that the invention provides a bolt type locking device having novel yet simple structure which not only enables it to perform its intended latching and unlatching function in association with a closure to which it is attached, but also provides means whereby when the device is employed-with massive closures and the latter are accidentally shut While the bolt of the latch is in extended latching position, the bolt will be withdrawn into unlatched position without damage thereto.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention maybe practiced otherwise than as specifically described.

I claim:

1. In a locking device a housing having therein a longitudinally extending hollow channel open at one end and a longitudinal slot communicating with said channel near the opposite end thereof, said slot having an enlarged portion at one end, a bolt adapted for slidable movement within said channel and having a tongue at one end adapted to extend beyond the open end of said channel to a latching position, a pin member fastened at one end thereof to the other end of said bolt and positioned with its axis normal to the axis of said bolt, said pin member extending through said slot externally of said housing, a cover member encircling and in slidable engagement with the portion of said pin member external of said housing, said cover member having a shoulder adapted to rest within the enlarged portion of said slot to retain said bolt in the latching position, a first spring means for urging said bolt and said pin member toward said opposite end of said housing to an unlatching position, a second spring means for urging the shoulder of said cover member into engagement within the enlarged portion of said slot, and means associated with said shoulder and said enlarged slot portion to facilitate automatic disengagement of the shoulder and the slot and allow movement of said pin member from said enlarged portion of said slot to the opposite end thereof on the application of a predetermined force against the extended tongue of said bolt whereby the bolt is actuated to the unlatching position.

2. In a locking device a housing having therein a longitudinally extending hollow channel open at one end and a longitudinal slot communicating with said channel near the opposite end thereof, said slot having an enlarged portion at one end, an annular depressed support member about the inner periphery of said enlarged portion, a bolt adapted for slidable movement within said channel and having a tongue at one end adapted to extend beyond the open end of said channel to a latching position, a pin member fastened at one end thereof to the other end of said bolt and positioned with its axis normal to the axis of said bolt, said pin member extending through said slot externally of said housing, a cover member encircling and in slidable engagement with the portion of said pin member external of said housing, said cover member having a shoulder adapted to engage said annular depressed member to retain said tongue in the latching position, a first spring means for urging said bolt and said pin member toward said opposite end of said housing and actuating the tongue to the unlatching position, a second spring means for urging the shoulder of said cover member into engagement with said depressed annular support member, and means associated with said shoulder and said support member to facilitate automatic disengagement of the shoulder and the support member and allow movement of said pin member from the enlarged portion of said slot to the opposite end thereof on the application of a predetermined force against the extended tongue of said bolt whereby the tongue is actuated to the unlatching position.

3. In a locking device as defined in claim 2, wherein said last mentioned means comprises cooperating .curved surfaces on the shoulder of said cover member and on said depressed support member providing a camming action to maintain said shoulder seated within the enlarged portion of said slot when the tongue of said bolt is extended in latching position'and to permit automatic release and withdrawal of said shoulder from the enlarged portion of said slot and consequently movement of said pin member to the opposite end of said slot on the application of a predetermined force against the exposed tongue of said bolt as aforesaid, urging said bolt in a direction to withdraw the tongue thereof into unlatched position within said housing.

4. In a locking device a housing having an open end, a closed end, a longitudinally extending -hollow channel communicating with said open end and a longitudinal slot communicating with said channel near the closed end of said housing, said slot having an enlarged arcuate portion at one end thereof and a narrower elongated portion at the other end, a depressed support member about the inner periphery of said arcuate portion, said support member being gently upwardly curved at its ends adjacent the elongated portion of said slot to form a first cam surface, a latch bolt positioned within said channel and adapted for slidable movement therein, said latch bolt having a tongue at one end adapted to extend outwardly to a latching position beyond the open end of said channel, a screw threadably engaging the other end of said latch bolt and positioned with its axis normal to the axis of said bolt, said screw extending freely through said slot externally of said housing, a sleeve encircling the portion of said screw external of said housing, said sleeve having a lower portion in slidable engagement with said screw and forming a shoulder at its base adapted to rest on said depressed support member, the outer edge of said shoulder being gently rounded to form a second cam surface, a stop member attached to the inside surface of said housing intermediate its ends and extending into said channel, a first spring within said housing encircling said latch bolt between said stop member and said screw, said spring urging said latch bolt and said screw toward the closed end of said housing to an 'by slidable movement of said cam surfaces relative to each other and consequent movement of said screw along said slot to the opposite end thereof on the application of an inward longitudinal force against the outwardly extending tongue of said latch bolt, urging said bolt in a direction to withdraw the tongue thereof into unlatched position within said housing.

References Cited in the file of this patent UNITED STATES PATENTS 89,191 Arnold et al. Apr. 20, 1869 1,298,861 Babbitt Apr. 1, 1919 1,510,562 Segal Oct. 7, 1924 FOREIGN PATENTS 2,173 Great Britain Sept. 3, 1863 

